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Ziniu Yu

Publications and source records attributed to Ziniu Yu.

25 records · Page 2Linked to original sources
PubMed2003

Genetic linkage map of the eastern oyster Crassostrea virginica Gmelin.

Amplified fragment length polymorphisms (AFLPs), along with some microsatellite and Type I markers, were used for linkage analysis in Crassostrea virginica Gmelin, the eastern oyster. Seventeen AFLP primer combinations were selected for linkage analysis with two parents and their 81 progeny. The 17 primer combinations produced 396 polymorphic markers, and 282 of them were segregating in the two parents. Chi-square analysis indicated that 259 (91.8%) markers segregated in Mendelian ratio, while the other 23 (8.2%) showed significant (P < 0.05) segregation distortion, primarily for homozygote deficiency and probably due to deleterious recessive genes. Moderately dense linkage maps were constructed using 158 and 133 segregating markers (including a few microsatellite and Type I markers) from male and female parents, respectively. The male framework map consisted of 114 markers in 12 linkage groups, covering 647 cM. The female map had 84 markers in 12 linkage groups with a length of 904 cM. The estimated genome length was 858 cM for the male map and 1296 cM for the female map. The observed genome coverage was 84% for the male and female map when all linked markers were considered. Genetic maps observed in this study are longer than the cytogenetic map, possibly because of low marker density.

Animals↗
PubMed2002

Determination of poly-beta-hydroxybutyric acid in Bacillus thuringiensis by capillary zone electrophoresis with indirect ultraviolet absorbance detection.

A new capillary electrophoresis method for determining poly-beta-hydroxybutyric acid (PHB) in Bacillus thuringiensis was established. Poly-beta-hydroxybutyric acid in samples was hydrolyzed by sulphuric acid and neutralized by Ba(OH)2. The content of produced beta-hydroxybutyrate was then determined by capillary zone electrophoresis (CZE) with indirect UV detection at 254 nm. With 5 mM p-hydroxybenzoate and 0.5 mM tetradecyltrimethylammonium bromide (TTAB) at pH 8.0 as carrier electrolyte, beta-hydroxybutyrate can be determined within 6 min. Standard regression equation was made by beta-hydroxybutyrate, and the linear range was 2-1000 microg/ml. The relative standard deviations (RSDs) for migration time and peak area are both less than 1.0%. The detection limit for beta-hydroxybutyrate was 0.2 microg/ml, which is two to three orders of magnitude lower than that of the gas chromatography (GC) method. The capillary electrophoresis method was successfully applied to determine poly-beta-hydroxybutyric acid in fermentation broth and single colony. The added standard recovery was 96%.

Bacillus thuringiensis↗
PubMed2002

[The cloning of plasmid replicon ori165 from Bacillus thuringiensis subsp. thenebrionis].

An EcoRI DNA fragment containing the plasmid replicon, named ori165, was cloned from the plasmids of B. thuringiensis subsp. tenebrionis strains YBT-1765. The replicon ori165 was the first replicon cloned from this subspecie. Its size is approximately 11 kb. The replicon was minimized to an 8 kb fragment by deletion analysis. Southern hybridization exhibited that ori165 was coming from the plasmid detected with the highest molecular weight. A shuttle vector pBMB6071 based on ori165 was constructed. The stabilities of pBMB6071 in different B. thuringiensis host had great discrepancy. In strain 4Q7, a crystal-negative derivative of B. thuringiensis subsp. isrealensis, the stability was 100%. ori165 was compatible with ori1030 and ori2062 in strain BMB171, a crystal-negative derivative of B. thuringiensis subsp. kurstaki.

Bacillus thuringiensis↗
PubMed2002

[Study on amount and stability of cry1D and cry1Ab mRNA in Bacillus thuringiensis subps aizawai].

cry1Ab, cry1C and cry1D are three typical cry1 class genes encoding protoxins in Bacillus thuringiensis subsp. aizawai strain HD-133. The expression of cry1D is obviously different from that of cry1Ab in this strain. Amount and stability of cry1D and cry1Ab mRNA in HD-133 were investigated. Northern blotting analysis showed that cry1D mRNA was more stable than cry1Ab mRNA, however, cry1D mRNA formed later 3 h and less 3.7 times than cry1Ab mRNA during the mid-phase of sporulation. Halve lives of cry1D mRNA was 18 min, but halve lives of cry1Ab mNRA was 14 min. Moreover, cry1Ab mRNA could keep stable and large amount during the post-phase of sporulation. This suggested that difference of transcriptional efficiency and initiate time might be main reason for the difference of expression of cry1Ab and cry1D.

Bacillus thuringiensis↗
PubMedDate not supplied

Genetic analysis of selected strains of eastern oyster (Crassostrea virginica Gmelin) using AFLP and microsatellite markers.

Amplified fragment length polymorphisms (AFLPs) and microsatellite markers were used to examine genetic variation and divergence in 4 selected strains (DBH, NEH, FMF, and CTS) and 1 wild population (DBW) of the eastern oyster Crassostrea virginica Gmelin. Eighty-six AFLP markers (from 3 primer pairs) and 5 microsatellite loci were used for the analysis of 30 oysters from each of the 5 populations. Microsatellite loci were considerably more variable than AFLPs. The observed heterozygosity ranged from 0.560 to 0.640 across populations for microsatellites, and from 0.186 to 0.207 for AFLPs. Both Fst and phiPT of microsatellite data and phiPT statistics of AFLP data revealed significant divergence between all pairs of populations. There was no significant reduction in heterozygosity in all 4 selected strains; however, the number of alleles per locus was considerably lower in the selected strains than in the wild population. Two strains subjected to long-term selection for disease resistance shared frequency shifts at a few loci, which deserve further analysis to determine if they are linked to disease-resistance genes.

Analysis of Variance↗
PubMedDate not supplied

Thermochemical characteristics of 2,4-dichlorophenol degrading strain Pseudomonas GT241-1 of growth metabolism by microcalorimetry.

By using LKB-2277 Bioactivity Monitor, ampoule method, the heat output of the growth metabolism of a 2.4-dichlorophenol degrading bacteria strain, Pseudomonas strain GT241-1, has been determined at 30 degrees C. From the thermogenic curves, it can be established that thermokinetic equation of their growth metabolism is Pt = Pt = 0 exp(k(m) t), dP/dt = k(m)P1, with the order of growth metabolism n = 1. The experimental results indicate that the relationship between the metabolic power (P) and the cell concentration (C), and relationship between the metabolic power of each cell (P0) and the cell concentration can be characterized by the following thermal equation: C = a + kP, InC = a' + k'P0 or dC/dP0 = KC1. The order of the P0-C equation n is also 1. These results are very significant in environmental sciences, biology and thermochemistry.

Biodegradation, Environmental↗